A number of web-based applications have been developed that allow patients to enter their own medical information into personal medical records. These applications are limited in their ability to serve as resources for self-monitoring of therapy, largely due to inherent problems related to ensuring the accuracy of patient-entered information. Focusing on patients with a range of thyroid conditions, I plan to evaluate different approaches to the collection, organization, and display of medical information. Attention will be focused on identification of methods of entry that enable patients to establish accurate diagnoses, confirm prescription information, and report specific test results. Selected approaches will be -implemented as part. of a web-based application dedicated to self-monitoring of thyroid hormone therapy. Use of this application will be evaluated with validated instruments, measuring patient acceptance, satisfaction, understanding of disease, and estimated compliance with therapy.